Patent US1551393A successfully refreshed from Google Patents.
US3728652A
Expired / Lapsed
US
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Ratus and arrangement thereof
Assignee: Canon Inc
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Filing: 1970-07-18
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Granted: 1973-04-17
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Expires: 1990-07-18
Abstract
Abstract A key apparatus includes a magnetic reed switch and at least one magnet forming a magnetic portions for energizing the reed switch. the magnetic portion having a plurality of magnetic poles disposed to produce substantially parallel magnetic fluxes opposite in sense so that the reed switch is maintained open under the influence of both of said substantially parallel magnetic fluxes opposite in sense when the key is in normal position and that the reed switch is closed under the influence of one of said magnetic fluxes. A plurality of such key apparatuses are arranged so as to form columns and rows and in such a manner that all the magnetic portions in any common column or row faces in the same direction but that the adjacent magnetic portions in any common row or column face in opposite directions, whereby the key board can be compact.
Inventors
- 👤 T Nishikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:52
CPC Classifications
B; B41; B41J; B41J5/00; B41J5/08; H; H01; H01H; H01H36/00; H01H36/0006; H01H36/004
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
195 words
A key apparatus comprising a key movable into an operative position by an external force applied thereto and returnable to a normal position upon release of said external force, a member movable in response to movement of said key, a magnetic unit secured to said member for generating substantially parallel magnetic fluxes at fixed spaced intervals and having opposite polarity, comprising a first magnetic portion having opposite poles and a second magnetic portion having opposite poles, the polarity of the poles of said second magnetic portion being oppositely disposed with respect to the polarity of the poles of said first magnetic portion, the first magnetic portion being magnetically separated from the second magnetic portion by a nonmagnetized region, and a reed switch disposed adjacent to and spaced from said magnetic unit and having two contact elements enveloped therein, said reed switch keeping said contact elements opened when said key is in the normal position, and said reed switch being operated to close said contact elements under the influence of a substantial flux component generated by one of said first and second magnetic portions of said magnetic unit when said key is in the operative position.
Claim 2
Dependent Claim
195 words
A key apparatus comprising a key movable into an operative position by an external force applied thereto and returnable to a normal position upon release of said external force, a member movable in response to movement of said key, a magnetic unit secured to said member for generating substantially parallel magnetic fluxes at fixed spaced intervals and having opposite polarity, comprising a first magnetic portion having opposite poles and a second magnetic portion having opposite poles, the polarity of the poles of said second magnetic portion being oppositely disposed with respect to the polarity of the poles of said first magnetic portion, the first magnetic portion being magnetically separated from the second magnetic portion by a nonmagnetized region, and a reed switch disposed adjacent to and spaced from said magnetic unit and having two contact elements enveloped therein, said reed switch keeping said contact elements opened when said key is in the normal position, and said reed switch being operated to close said contact elements under the influence of a substantial flux component generated by one of said first and second magnetic portions of said magnetic unit when said key is in the operative position.
Claim 3
Dependent Claim
33 words
A key apparatus as defined in claim 1, wherein said first and second magnetic portions comprise magnets respectively, and said magnets are disposed spaced from each other to form a magnetic gap therebetween.
Claim 4
Dependent Claim
31 words
A key apparatus as defined in claim 1, wherein said reed switch is disposed closely spaced from and in substantially parallel relationship with respect to said first and second magnetic portions.
Claim 5
Dependent Claim
160 words
A key apparatus comprising a key movable into an operative position by an external force applied thereto and returnable to a normal position upon release of said external force, a member movable in response to the movement of said key, a magnetic unit comprising two magnet means each having different magnetic flux density and disposed in parallel with each other for generating substantially parallel magnetic fluxes at fixed spaced intervals and having opposite polarity and a reed switch, having two contact elements enveloped, disposed at an area where said magnetic fluxes generated by said two magnet means interact with each other and closely spaced from said magnet means, said reed switch keeping said contact elements opened when said key is in the normal position, and said reed switch being operated to close said contact elements under the influence of one magnet means having higher magnetic flux density than the other magnet means when said key is in the operative position.
Claim 6
Dependent Claim
160 words
A key apparatus comprising a key movable into an operative position by an external force applied thereto and returnable to a normal position upon release of said external force, a member movable in response to the movement of said key, a magnetic unit comprising two magnet means each having different magnetic flux density and disposed in parallel with each other for generating substantially parallel magnetic fluxes at fixed spaced intervals and having opposite polarity and a reed switch, having two contact elements enveloped, disposed at an area where said magnetic fluxes generated by said two magnet means interact with each other and closely spaced from said magnet means, said reed switch keeping said contact elements opened when said key is in the normal position, and said reed switch being operated to close said contact elements under the influence of one magnet means having higher magnetic flux density than the other magnet means when said key is in the operative position.
Claim 7
Dependent Claim
42 words
A key apparatus as defined in claim 4, wherein said reed switch is normally located adjacent the spaced area between said two magnet means disposed in parallel, and one magnet means is brought into an opposed position upon depression of said key.
Claim 8
Dependent Claim
195 words
A key arrangement comprising a plurality of key apparatus arranged in a matrix array eAch comprising a key movable into an operative position by an external force applied thereto and returnable to a normal position upon release of said external force, a supporting member movable in response to movement of said key, a magnetic unit comprising a first magnetic portion having opposite poles and a second magnetic portion having opposite poles, the polarity of the poles of said second magnetic portion being oppositely disposed with respect to the polarity of the poles of said first magnetic portion, the first magnetic portion being magnetically separated from the second magnetic portion by a non-magnetized region, and a reed switch disposed spaced from and in parallel relationship with said first and second magnetic portions and perpendicular to the moving direction of said supporting member, wherein each reed switch opposed to its respective magnetic unit on one column in said matrix array is arranged on one side with respect to each supporting member, and each reed switch opposed to its respective magnetic unit on the adjacent column is arranged on the opposite side with respect to each supporting member.
Claim 9
Dependent Claim
195 words
A key arrangement comprising a plurality of key apparatus arranged in a matrix array eAch comprising a key movable into an operative position by an external force applied thereto and returnable to a normal position upon release of said external force, a supporting member movable in response to movement of said key, a magnetic unit comprising a first magnetic portion having opposite poles and a second magnetic portion having opposite poles, the polarity of the poles of said second magnetic portion being oppositely disposed with respect to the polarity of the poles of said first magnetic portion, the first magnetic portion being magnetically separated from the second magnetic portion by a non-magnetized region, and a reed switch disposed spaced from and in parallel relationship with said first and second magnetic portions and perpendicular to the moving direction of said supporting member, wherein each reed switch opposed to its respective magnetic unit on one column in said matrix array is arranged on one side with respect to each supporting member, and each reed switch opposed to its respective magnetic unit on the adjacent column is arranged on the opposite side with respect to each supporting member.
References Cited (Backward Citations)
US3260819A
Cited
US3533029A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |